A new high performance auto-tuning digital control circuit for buck-boost converter

The purpose of this paper is to present the dynamic characteristics of the new high performance auto-tuning digital control circuit for buck-boost converter when the step change of the load resistance R from 20 Ω to 10Ω. The buck-boost dc-dc converter is used with wide input voltage changing. At the same time, the suitable proportional gain and bias value are changing against the input voltage and the load resistance of the converter. So, we took two methods that changing proportional gain automatically and changing bias value against the input voltage, the load resistance and the loss of the converter. As a result, using this proposed method it is revealed that not only the dynamic characteristic but also regulation characteristic can be improved and it is effective for wide range input voltage. Especially, the steady-state error is improved from 470mV to 50mV when the input voltage is 5V, 700mV to 40mV when the input voltage is 15V, respectively.